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OITT D 0 O IT MEN T. — No. 108 . 


BOSTON HARBOR: 

A SERIES OF COMMUNICATIONS 


TO THE 


BOSTON DAILY ADVERTISER, 



BENJAMIN A. GOULD, 


REPUBLISHED BY ORDER OF THE CITY COUNCIL OF BOSTON. 


✓ 



BOSTON: 

J. E. HARWELL & COMPANY, PRINTERS 

37 Congress Street. 
1863. 


TO THE CITY, 














lo'IM 


CITY OF BOSTON. 



In Board of Aldermen, December 7, 1863. 

Ordered : That the Committee on Printing be authorized 
to have printed, with the permission of the author, for the use 
of the City Council, five hundred copies of the articles on 
“Boston Harbor,” recently published in the “Daily Adver¬ 
tiser.” 

Sent down for concurrence. 

THOMAS C. AMORY, Jr., Chairman . 

In Common Council, December 10, 1863. 

Concurred. 

■ GEORGE S. HALE, President . 

Approved, December 12, 1863. 

F. W. LINCOLN, Jr., Mayor. 



* 




COMMUNICATIONS. 


NUMBER I. 

Under the title of “ Communications and Reports 
in Relation to the Surveys of Boston Harbor,” the 
series of Reports of the present Harbor Commission 
have recently been bound up together and issued in a 
neat volume by the City Government, together with 
impressions of as many of the maps and tracings 
as are requisite for a general understanding of the 
subject. 

Although of course every Bostonian is interested 
in the preservation of the once admirable Harbor to 
which all the prosperity of our City is due, and 
though the importance and wealth derived from its 
commerce has in fact been one of the principal 
sources of the intellectual pre-eminence of New 
England; yet, only those few who have given careful 
study to the subject seem to be at all aware of the 
alarming deterioration which it has suffered in recent 
years. 

Not only have the Islands, once so beautiful, — the 



6 


protection of the roadsteads and the guards of the 
channels, — been destroyed to a startling extent by % 
the action of winds and waves for want of the arti¬ 
ficial protections which became a necessity, at least 
for their headlands, after the original safeguards of 
ballast-shingle, trees, and grass had been removed ; 
not merely, in addition, have the channels filled 
up, the flats extended and shallowed, new shoals 
formed and old shoals grown larger, but the hand 
of man has recklessly destroyed natural agencies on 
which the harbor depended for • protection, and has 
called into action other influences detrimental to an 
extraordinary degree. 

It was doubtless by the discovery or keenly awak¬ 
ened sense of the danger which actually threatened 
annihilation to the commercial prominence of our 
City, — already waning, and indeed undeniably dimin¬ 
ished relatively to other seaports of the Northeast, — 
that our excellent Mayor, during a former term of 
office, took those steps which led, through his con¬ 
tinued exertions, to the appointment of the present 
Harbor Commission. In a message to the City 
Council, in 1859, he called their attention earnestly 
to the subject, and urged the appointment of a 
Scientific Commission to investigate the changes in 
the harbor. We will quote from his communication 
of October 24: — 


7 


4 4 The prosperity of our city is intimately connected with 
its foreign and coastwise commerce. Its situation on the 
Atlantic seaboard, having one of the best harbors in the 
world, has given it its rank as one of the most important 
maritime ports of modern times. Anything which endangers 
the safety of its harbor, caused either by the hand of man 
or the ravages of the sea, should be watched with jealous 
scrutiny and care. 

44 Its local importance to ourselves as well as to the Com¬ 
monwealth, of which we are the capital, cannot be over-esti¬ 
mated, but it has a national importance equally significant, 
for within its waters is established one of the best of the naval 
stations of the Union, and through its Custom House a large 
portion of the Revenues for the support of Government are 
collected. Boston Harbor does not belong to Boston alone, 
but to the whole Nation; and we are recreant to duty if, 
living in the immediate vicinity, we do not adopt all those 
instrumentalities which shall secure its safety.” 


4 4 Recent investigations have shown that the time is come 
for some energetic measures, which shall embrace the lower, 
as well as the upper harbor. In the former, islands and 
headlands are washing away, the ship-channel is becoming 
narrow, and symptoms are every day developing, the results 
of which will be disastrous if not speedily checked and 
abated. 

“The National Government has done much, by the strength 
and character of its fortifications, to assure our safety from 
the attack of the foreign fleets of an enemy; but their atten- 


N 


8 

tion should now be solicited to those insidious assaults of the 
sea, which are constantly undermining and putting in jeop¬ 
ardy the integrity of our harbor. Through the exertions of 
one of our late representatives in Congress, Mr. Comins, a 
bill was reported at the last session from the Committee on 
Commerce, making an appropriation for a scientific survey. 
The bill failed to pass the House,—not so much, I under¬ 
stand, from an indisposition to aid the matter, as from a 
want of knowledge of the facts which would justify such an 
appropriation. In this dilemma, following the example of 
other cities, I would suggest for your consideration the ap¬ 
pointment of a Commission for the examination of the subject. 
These Commissioners should be of high scientific attainment, 
of much experience in the examination of tidal waters and 
oceanic currents, free from any local bias, and whose testi¬ 
mony would be of weight in the Congress of the United 
States. Some tangible facts from a source which cannot 
be questioned, must have an influence upon that body.” 

Fortunate enough was it for Boston that, even at 
that time, the interest of the official fathers was 
invoked. A very few years more and it would have 
been too late. Not Mayor Lincoln, not the mer¬ 
chants, not even the pilots, were fully aware of the 
extent of the deterioration of the harbor, nor of the 
alarming and actually increasing rate at which it was 
going on. 

The “ Joint Standing Committee on the Harbor ” 


9 


— for such a Committee of the City Council had 
long existed — reported without delay, cordially ap¬ 
proving the recommendations of the Mayor, and 
proposing the necessary legislation. Orders were 
passed at once authorizing the Mayor to invite 
General Totten, Professor Bache, and Commander 
Davis, to act as Commissioners to investigate and 
report upon the condition of the harbor, with a view 
to its preservation and safety ; and furthermore, the 
consent of these gentlemen being obtained, to solicit 
the executive departments at Washington to detail 
them — all being officers in the United States service 

— for this special service. The necessary official 
action at Washington was obtained through the 
personal exertions of Mayor Lincoln; and since 
November, 1859, the three gentlemen already named 
have gratuitously served as a Harbor Commission for 
the City of Boston. They have already planned, 
organized, and superintended three distinct surveys, 
executed by the assistance of the Coast Survey and 
its officers; and have presented six important and 
elaborate reports, beside sundry minor communica¬ 
tions. If their warnings are but heeded, and those 
counsels which are the abundant fruit of their labors 
can be permitted to ripen into practical action, unborn 
generations may be grateful that Boston remains a 
centre for commerce, science, letters, and art. 


2 


10 


The earliest full report of the Commissioners was 
in March, 1860. It stated that the City Government 
had in no degree over-estimated the serious and inju¬ 
rious changes which were going on in the harbor ; 
that the encroachments of the sea were destroying 
the headlands and islands; that channels had grown 
dangerous to vessels of deep draught, having become 
narrower in some places, and the deep water being 
so much encroached upon, that where the pilot-boats 
were not long since accustomed to run boldly up to 
a steep shore, to land their crews or to lie to during 
a gale, shoal ground now precluded their approach. 
Also, that the navigable part of the inner harbor had 
lost in area, the width of the channel become less, 
and its direction altered. 

They presented, without formal recommendation, 
though with sufficient distinctness to indicate their 
opinion of the importance of the respective exami¬ 
nations/estimates of the cost of a new hydrographic 
survey of the main ship-channel, of a topographical 
survey of the shores and islands of the lower harbor, 
and of a series of gauges and current observations, 
in the Charles, Mystic, and Neponset rivers. And 
they added two distinct recommendations : — 

In the first place, that prompt and effectual meas¬ 
ures be taken to prevent the removal of any more 
material from Gallop’s, and the other islands of the 


11 


harbor; and that the former be taken out of private 
hands, if possible, and put into public keeping. 

In the second place, that the existing water area 
be preserved until some plans and some principles 
should be recognized and adopted by which private 
interests may be subserved without the sacrifice of 
the public good. 

These recommendations were complied with. The 
title to Gallop’s Island was promptly and judiciously 
secured by the City, and a temporary check was 
placed upon the numberless encroachments which 
were so rapidly sacrificing the permanent prosperity 
of the City to the temporary aggrandizement of reck¬ 
less individuals. 

During the summer of 1860, maps were con¬ 
structed for exhibiting the changes which had 
occurred in the inner harbor. The results of the 
examination were such as to lead to a special com¬ 
munication from the Commission to the City Gov¬ 
ernment on the 2d of November. They announced 
that the changes had proved to be of a striking 
and even alarming nature; that they regarded it 
as of the highest importance that a new and very 
minute survey of the inner harbor should be made, 
— covering the same ground as that of the survey 
in 1835-6, — and strongly urged this upon the City. 
The Municipal Government responded at once, the 




12 


t 


Committee on the Harbor earnestly advocating the 
survey, and the City Council, by a unanimous vote 
in each branch, requested the Commissioners to 
make the survey suggested, and appropriated eight 
thousand dollars for the purpose. This survey is 
now mostly completed. 

There are thus available at present for the detec¬ 
tion of the changes, the study of their laws, and the 
discovery of their causes,— 

1. The survey of the inner harbor by the first 
Commission, which was appointed by the State, in 
1835, and consisted of Messrs. Baldwin, Thayer, and 
Hayward. 

2. The survey of the entire harbor, executed in 
regular course, by the United States Coast Survey, in 
1847. 

3. The hydrographic survey of the main ship- 
channel, in 1860. 

4. The topographical survey, in 1860, of the 
shores and islands of the lower harbor north of 
42° 18'. 

5. The series of river gauges and current obser¬ 
vations executed, on an extended scale, during 1860 
and 1861. 

6. The minute survey of the inner harbor, by the 
present Commission, begun in 1860, and now essen¬ 
tially completed. 


13 


From these materials the desired information may 
be deduced without much difficulty. 

And although the injuries inflicted upon the harbor 
by the hand of man, during the last fifteen years, 
are beyond the power of man to repair; although 
we cannot reasonably hope that the harbor will 
ever be restored to the excellent condition in which 
it was delivered over by the last generation to the 
present, it is perhaps not too late to remedy some 
of the injury, and it is certainly within our power 
to arrest the progress of encroachment. 


NUMBER II. 


We have recently given an historical summary of 
the circumstances connected with the appointment of 
the Boston Harbor Commission, and a brief statement 
of the character of their labors hitherto, so far as we 
have seen the published results. They have reported, 
among other things,— 

That the headlands of the harbor are rapidly wash¬ 
ing away in many places. 

That new spits, or submerged points of land and 
new shoals are forming, and in dangerous positions. 

That the channels are losing in width, in depth, 
and, in some places, in directness. 

That the flats are in many places rising, and in 
general extending, so that the navigable area of the 
inner harbor is essentially diminished. 

That these changes are of a magnitude already 
quite detrimental to navigation, and that the agencies 
which produced them are still actively at work, and 
in some cases with increased activity. 

Such a state of things may well arouse the most 
phlegmatic, exciting the apprehensions and demand- 


15 


ing the exertions of every true Bostonian. Can we 
not act speedily and vigorously'? How shall we act ? 
And how combine our individual efforts to remedy 
whatever is not past remedy, and to mitigate what¬ 
ever cannot be entirely obviated] 

With a view to answering these and similar ques¬ 
tions, we have carefully and earnestly studied the re¬ 
ports of the Harbor Commission. And it would seem 
as though the simplicity of the laws which regulate 
and control the changes were such that none could 
fail to comprehend them; notwithstanding the obvious 
fact that here — as in all other cases where simple 
laws are acting simultaneously under different circum¬ 
stances — a complication must result, which those 
unacquainted with the subject are too apt to refer to 
some complexity in the laws, rather than to its true 
origin in the variety and diversity of the circumstances 
under which they find application. 

Let us consider for a moment what are the chief 
influences which may act upon a harbor for good or 
ill, and then it will doubtless be comparatively easy 
for us, who know the local relations, and are now 
provided with the fundamental facts, to reduce our 
special inquiry within tolerably narrow limits ; even 
though we should not be able to attain to a distinct 
and complete answer. 

It is self-evident that a permanent harbor or chan- 




16 


nel cannot exist, except where either no constant in¬ 
jurious influences are at work, or where such influ¬ 
ences are balanced and entirely defeated by other 
agencies of a beneficial character; and furthermore, 
that any such balance of influences must be essen¬ 
tially a state of stable equilibrium, else in the course 
of years it would have been long since overthrown. 
Harbor changes may thus be reasonably attributed in 
every case either, in the first place, to some general 
influence affecting the entire region, such as the ele¬ 
vation or subsidence of a coast, — to the progress of 
some regular deposit or detrition reaching a limit 
toward which it had long been tending, and its effect 
upon which might for a long time previous have been 
foreseen; or, in the second place, to some special in¬ 
fluence which is in most cases attributable to human 
agency, — although sometimes due to earthquakes, 
volcanic eruptions, or some other sudden natural ca¬ 
lamities. 

But where, as in our own case, the natural adjust¬ 
ment has been evidently disturbed, and that equipoise 
of natural influences which, in past ages, constructed 
and has since maintained Boston Harbor, has been 
overthrown, we must, look to some comparatively 
recent influence to explain any recent change. This 
is certain. 

Now what makes a channel? A running stream 


17 


which has sufficient power to form for itself a bed ; 
or, in other words, which can exert scouring force 
adequate to the displacement and removal of some of 
the materials over which it Hows. If this material be 
sandy gravel, a velocity equivalent to its half-a-mile 
an hour is found, by experiment, to be requisite for 
such displacement; if ,fine beach sand, three tenths 
of one mile an hour will suffice, — and the needed 
velocity is, of course, less for simple mud and greater 
for coarse stones. And a stream the force of whose 
current is ever sufficient to bring about this scouring 
velocity at the bottom will wear for itself a channel, 
even though its bed be dry for eleven months out of 
the twelve. The same principle applies moreover 
when, as in the case of harbor channels, the bed 
is never dry, or even visible; and it is clear that, if 
a stream meets the tide with the bottom velocity of 
only one tenth of a mile an hour over a gravelly bed, 
this will be sufficient to scour out for itself a chan¬ 
nel, provided the ordinary tidal how can supply the 
remaining four tenths of a mile an hour. For, even 
were the tidal flow one half a mile an hour at the 
bottom, its inward force would be decreased by the 
outflow of the stream to a velocity of four tenths, 
which could transport none of the material up stream; 
while the force at ebb, composed of the tide-flow and 
the river current combined, would be equal to an 


3 


18 


hourly rate of six tenths of a mile,—and thus move 
the material of the bottom seaward twice a day. In 
this way a channel necessarily results wherever a 
stream has sufficient force for the average velocity of 
outflow at the bottom, when combined with the tidal 
current, to remove the material of the bed, either by 
rolling or by washing away. No matter how great 
the tidal force, or how great the semi-diurnal motion 
of the materials of the channel-bed inwards ; if any 
river current whatever exist, the semi-diurnal outward 
motion will be greater yet, and a channel will be the 
inevitable result. So too if by reason of the confor¬ 
mation of the shore, the outward tidal current at all 
exceed the inward in velocity at the bottom, the same 
result ensues, provided only that the outflow be com¬ 
petent to the removal of the material at all. 

Again, if a current, bearing with it rolling gravel 
and sand, be—by reason of any sudden expansion 
of the channel through which a given amount of water 
is discharged in a given time—reduced to a velocity 
below the scouring limit, the material is deposited at 
that point where the scouring velocity ceases to exist. 
If, however, the material moved by the current be 
finer and lighter, so that it is in any degree held in 
suspension, the loss of scouring velocity does not 
necessarily require that the deposit be immediate ; 
but the material mostly remains in suspension, set- 


19 


i 


ling slowly to the bottom as the current flows on, 
and being chiefly deposited where the current ceases. 
In this way bars or shoals are formed at those places, 
near the mouths of streams, where the outward flow 
is suddenly provided with increased facilities for its 
discharge, occasioning diminution of velocity; or where 
in consequence of conflicting currents slack water oc¬ 
curs, either permanently or at regular tidal intervals. 

These considerations sufhce to show the importance 
of maintaining river currents, no matter how small, 
and tidal reservoirs, so called, — provided those chan¬ 
nels, which have been occasioned by their outflow, 
need to be maintained. The agencies of nature are 
always active, — if not for us, they are against us; 
and the equilibrium of nature is never one of stagna¬ 
tion, but arises always from an equipoise of motion 
and force, — either active or ready to become so. No 
channel will remain a channel if the producing forces 
cease to be maintaining forces. If there be no scour 
of the bed, there will be a deposit. The channel will 
either be maintained, or will begin to be obliterated. 

If a tidal current, of any degree of strength above 
the scouring limit, set alternately as the tide ebbs and 
flows, the material of the channel-bed will be swept 
inward with the flood and outward with the ebb. 
And it is manifest that where the amount of inward 
and outward transportation of the material is equal, 


20 


no permanent change of the channel can be brought 
about; but that if either predominate, as is the case 
when the duration of ebb and flow are unequal, or when 
the conformation of the shore gives them unequal 
force, a change, either for good or ill, must neces¬ 
sarily take place. One more element must however 
not be overlooked; viz: the different character of dif¬ 
ferent tides. For no estimate of the permanent effect 
of tidal action will be accurate which is founded on 
consideration of the average tides only, omitting that 
of spring-tides and freshets. The effect of the latter 
is almost uniformly favorable to the maintenance of 
channels; for the increased volume of water at the 
flood fails by reason of its depth to exert on the 
channel-bed any inward scour at all commensurate with 
the outward one, which is produced by the current 
at the very low water of the corresponding ebb. 

The principles thus laid down — rather broadly it 
is true, lest, in an attempt to express ourselves with 
strict scientific precision, the clearness of explanation 
be too much sacrificed — are entirely adequate to 
the explanation of a large part of the phenomena 
observed in Boston Harbor. When taken in connec¬ 
tion with the contour of the shore at different stages 
of the tides, and with the form of the bottom, they 
will answer the most important of the inquiries rela¬ 
tive to its impending destruction. They may be essen¬ 
tially summed up as follows : — 


21 


The preservation of a channel must depend upon 
the constant, or at least continually recurring action 
of a maintaining force. This maintaining force must 
arise from a friction of the water in contact with the 
bed, sufficient to wear or roll away part of the mate¬ 
rial of which the bed is composed, or such matter 
as may be deposited there; and furthermore if, as 
in the case of tidal channels, the motion be in differ¬ 
ent directions at different times, the motion in one 
of these directions must sufficiently predominate to 
prevent the material which is removed at one time 
from being restored to its original position when the 
current is reversed. That the channel may be a con¬ 
tinuous and useful one, the predominant motion must 
be outwardly, and the desired effect may be secured 
in three principal ways. 

1. By the outflow of a river, or even a stream 
too small to deserve that name, yet competent to give 
the needed predominance of outward motion, — espe¬ 
cially at the lowest ebb, or where the unassisted tidal 
current approaches without usually attaining the force 
requisite for producing a scour. 

2. By the outflow of “ tidal reservoirs,” which 
receive, during the rise of the tides, a volume of water 

to be discharged along the channel with greater effect 

# 

on the bottom when the tide is low. Meadows and 
lowlands, which are overflowed during extraordinarily 


22 


high tides, often contribute no unimportant aid in this 
way. 

3. By a contour of the shore line or even of the 
bottom, which leads the outflowing current along a 
different path from the inflowing one, or else confines 
the outflow within narrow limits, — thus giving to 
the same volume of water a greater velocity. 

If on the other hand two currents, each of which 
exerts a scouring force on its own channel, meet at 
a sufficient angle to bring the momentum of their 
current after confluence below the limit required for 
carrying away all the material which they bring with 
them to the place of meeting, — a shoal or bar is in¬ 
evitable. This is true, whether the currents be those 
of rivers, or the outflow of basins, or are due to the 
semi-diurnal fluctuations of the tide. And wherever 
at any time of tide or in any part of a stream, slack 
water occurs, or the water remains for a time in a 

state of comparative repose, we must expect a depo- 

• • 

sition as sediment, of the material previously held in 
suspension. But spring-tides and freshets are com¬ 
petent to remedy much of the difficuly thus arising, 
and by their influence many a channel is kept open 
from year to year, which is, during a great part of 
the time, subjected to detrimental influences. 


NUMBER III. 


In our last communication we endeavored to state, 

K 

in as brief compass as was compatible with distinct¬ 
ness, the general laws which control the formation, 
destruction, or maintenance of harbor and river chan¬ 
nels. Let us now inquire what constitutes a good har¬ 
bor, or rather what are the principal requisites for 
giving maritime value to a port. We say maritime 
value, because we are considering the question solely 
from the nautical side, without regard to those other 
requirements which affect its commercial importance, 
and the absence of which leaves some of the finest 
harbors in the world unfrequented. 

The sailor will tell us that he requires an easy 

• • 

access. The channel must not be tortuous, nor fre¬ 
quently shifting; the main approaches must be deep 
enough to float full-laden ships at the lowest stage 
of tide, and wide enough to be safe with ordinary 
care. Besides this he would ask for one or more good 
roadsteads, where his vessel may safely ride at anchor 
during heavy blows from any quarter, especially from 
seaward; in short, for room, anchorage, and shelter. 


24 


That the port should be accessible during any wind is 
also most desirable, though perhaps not indispensable. 

The merchant will tell us that he needs depth of 
water at the wharves, piers, or quays, that he may dis¬ 
pense with the awkward and expensive aid of lighters 
in loading and unloading cargoes. Yet the current 
must not run too violently against the wharves, so as to 
undermine them or render the moorings difficult, or 
create continual danger of collision. And the greater 
the line of wharf or quay frontage, possessing these 
qualifications, the more available is the port for his 
purposes ] 

Boston Harbor once possessed these requisites in an 
eminent degree. The long circuit of wharves which 
fringed the margin of the city; the admirable chan¬ 
nels, sweeping just past the ends of the wharves from 
the Back Bay, the South Bay, and the Mystic; the 
noble ship-channels, through the largest of which the 

largest frigate could stand boldly up to the city in an 

• 

almost straight course, while two thirds of the ship¬ 
ping could be accommodated by the others ; the mag¬ 
nificent and admirably sheltered roadsteads, inclosed 
by hilly islands; the excellent landing-places upon 
these islands; the fine bold headlands, beacons in 
themselves, to guide the pilot, or indeed to render his 
aid far less imperatively necessary, — all combined, 
within the memory of the present generation, to form 
a harbor of the first class. 


25 


\ 


To what influences are we to attribute the disastrous 
changes'? We know some of the general laws, so far 
as regards the formation of channels. What are the 
other laws concerned, and what is their especial 
application ? 

Perhaps it may be well to consider one or two 
other general principles, before passing to their local 
effects. 

And first, as to the formation of harbors in general. 
Omitting those which may be regarded as accidental 
nooks in rocky shores, where we have neither occasion 
nor opportunity for inquiry into causes or maintaining 
influences; also, such as owing to the absence or 
destruction of a maintaining force, are fast becoming 
useless to commerce, which is not an unfrequent case 
in regions where the gradual elevation or subsidence 
of the coast line is destroying the existing equilibrium, 
— we shall find that the harbors of alluvial shores 
belong to some one of three classes. 

First, those which are not situated at the mouth of a 
river, but owe their existence to an interior basin, the 
scouring action of whose outflow exceeds that of the 
inflowing current sufficiently to create and maintain 
the channel. To this class belongs Portland. 

Secondly, such as are simply the outlets of rivers, 
and are either without regular tides, or are so situated 
that the tidal action is not an important element in 


4 


26 


their preservation. Harbors of this class are gener¬ 
ally obstructed to some extent by a bar or shoal, occa¬ 
sioned by the subsidence or deposit of material which 
the water has borne along, until the enlarged facilities 
for outflow have so far diminished the velocity of the 
current that its transporting power is unequal to their 
further removal. To this class belongs Newbury port. 

Thirdly, such as are situated at the mouths of rivers 
and are provided also with tidal reservoirs, thus owing 
their existence and maintenance to both forces; and it 
is manifest from what has been already stated that the 
joint action of the two forces may suffice to produce 
and to preserve an excellent harbor, even in cases 
where neither alone would have proved adequate. To 
this class belongs Boston, with its three rivers and 
three principal tidal basins. 

And in any inquiry as to harbor changes, either for 
good or ill, originating either in natural or artificial 
disturbances of the existing equilibrium, we must keep 
in view both the joint and reciprocal action of these 
several producing and maintaining agencies. 

Next, as to the forms of channels in their relation 
to the ranges of the tides and the velocity of the cur¬ 
rent. The laws which rule here are well set forth and 
explained in the fifth report of the Commissioners, 
published as City Document No. 35, of the present 
year. 


27 


It is well known that where a bay or inlet is favor- 

V 

ablv situated for the entrance of the tide-wave, and 
decreases in width from its mouth upwards, the tides 
are increased in range; in other words, that the 
amount of rise and fall becomes greater and greater as 
the tide travels up a wedge-shaped bay. This arises 
from the concentration, so to speak, both of the vol¬ 
ume and the momentum of the inflowing water, occa¬ 
sioned by the convergence of the shores; and, recipro¬ 
cally, bv the reversed action at the outflow; and, 
conversely, when the tide-wave moves through a 
comparatively narrow inlet into an expanded basin 
it undergoes a “ degradation of range,” i. e. the extent 
of rise and fall is diminished as it spreads over the 
broader space within. “ Tidal currents ” are thus pro¬ 
duced by the effort of the water to bring about an 
equilibrium between the basin and the sea; and it is 
found bv observation, as a little reflection would lead 
us to anticipate, that their epochs or times of greatest 
intensity follow, not the times of high and low water, 
but the times of restored level between the basin and 
the ocean, which coincide nearly with the half tides. 

We will state one more principle, and then leave 
theory in order to pass to the practical application of 
these dry (though watery) laws. And we cannot state 
it better than by quoting the language of the Commis¬ 


sioners : — 


28 


» 


“ A contraction of a water-way augments the cur¬ 
rents, and tends to increase the depth of the movable 
stratum, calling into action scouring forces near the 
bed of the channel. When a stream meets with a 
contraction, it is partially dammed up, so that an 
increase of head is caused, which not only augments 
the current upon the surface, midway between the two 
shores, but, by the increase of vertical pressure, causes 
particles far below to take the effort for the restoration 
of equilibrium. The greater proximity of the banks of 
the channel increases but very little the friction of par¬ 
ticles moving along the central portion of the stream, 
so that their velocities are quickened nearly as much as 
they would be by an increase of head in an open bay. 

“We would not be understood to say that the in¬ 
crease of vertical pressure acts directly to increase the 
abrasion, but that it causes an increase of motion in 
the lower stratum, which scours away the channel-bed. 
It is often noticed that the water of a shallow stream, 
flowing into a deep lake or into the sea, continues to 
move on as a superficial current for a great distance ; 
but if after issuing from the mouth of the river it 
meets with a contraction of the channel, it at once 
communicates its motion to deeper strata. At such 
contractions the currents below the surface are often 

in excess of those on top.It seems to be the 

general rule that in a contraction the currents at a 



29 


central point, both as regards width and depth, have 
the greatest velocity. 

“ We see by this that it is a simple thing to call into 
action scouring forces by contracting a stream in a 
certain manner; but it has always been a difficult 
problem to dispose advantageously of the muds and 
sands which are removed from one point only to be 
accumulated at another. 

“ In the absence or scarcity of river waters, which 
tend to augment the ebb and check the flood-drift, the 
effects of irregularities in the widths of the water-ways 
in a tidal harbor are peculiarly disastrous. Sand is 
rolled along the bottom whenever the current exceeds 
0.30 miles per hour; but so short a distance is 
travelled by a rolling grain of sand during one 
tide, that should the adverse current (that of the 
next six hours) be exactly opposed in direction, and 
equal in velocity to the preceding, the grain of sand 
will roll back to its original position, and no increase 
of depth will follow. This is simply a repetition of 
the doctrine we have so frequently announced before, 
that rolling material is moved in the direction of 
the resultant of the current forces of one tidal day 
precisely as if these forces acted simultaneously. If 
these forces are in equilibrium at any point there is 
not only no removal but usually an accumulation, 
since the sand is rolled up to this point from either 
side.” 


30 


To sum up these results, in the fewest convenient 
words, we may state as follows : — 

That the range of the tide, i. e. its amount of rise 
and fall, is increased when, as in the Bay of Fundy, 
the tide-wave moves along a narrowing path, and is 
diminished when, as in the inlets of North Carolina, it 
traverses an expanding one ; the latter effect being 
greatest for an interior basin connected with the sea 
by a comparatively narrow inlet. 

That the times and velocities of the tidal currents 
do not directly follow the epochs of high and low 
water, although of course indirectly depending upon 
them. 

That these currents may undergo great changes 
as to their times and velocities, while the rate of the 
propagation of the tide-wave remains essentially the 
same. 

That irregularities in a channel are in general detri¬ 
mental, the contractions producing a scour which deep¬ 
ens the channel by the removal of material to be de¬ 
posited just below the expansions; these latter thus 
acting as shoaling agencies. 

That in this way every decided contraction in a tidal 
channel tends to produce shoalings of the channel both 
above and below; the one being created by the flood 
currents and the other by the ebb. 

We will now leave the scientific principles, and in 






31 


our next article will show the application of some of 
them to the case of Boston Harbor,—its original forma¬ 
tion, its present deterioration, and the possibilities of 
remedy. 


ii 


NUMBER IV. 


The outer harbor of Boston lies at the head of 
Massachusetts Bay, and may be regarded as bounded 
by the line, three miles in length, between the prom¬ 
ontory of Nantasket and the extremity of Deer 
Island, itself once a promontory, though now insu¬ 
lated by the narrow channel known as Shirley Gut. 
Along this line now lie Lovells, Gallop’s, and George’s 
Islands, which break the force of wind and wave; and 
in the same group with these was once a fourth, of 
which only the shoal called Nix’s Mate is left. Out¬ 
side of these were many more, only a few of which 
now remain, except in the uncomfortable shape of 
reefs and ledges. Among them may be mentioned 
the Three Brewsters, the two Calf Islands, Light¬ 
house Island, Green Island, and sundry others, now 
only known as this or that reef, or as somebody’s 
ledge, or as something’s or somebody’s rocks. Be¬ 
tween these rocks, or reefs, or ledges, are the ap¬ 
proaches to the harbor. The dangers on the seaward 
side are easily avoided, thanks to the Coast Survey, 
by the seaman furnished with chart and log line. 


33 


And all the various approaches for shipping finally 
converge to three, along some one of which every 
laden vessel must pass in entering or leaving port. 
These are the main ship-channel, which passes be¬ 
tween Lovell’s Island on the northeast and Gallop’s 
and George’s on the southwest, — the united Broad 
Sound channels, where two or more approaches from 
the northeast unite in one to the north of Lovell’s 
Island, — and the Back Way, which is on the south 
of George’s. 

The main ship-channel passes, between sundry rocks 
and shoals, through a passage called the Narrows, 
between the point of a spit on the one side, which 
extends southwest from the Great Brewster Island, and 
the Tower Bock on the other, a small submerged rock, 
dangerous to vessels drawing eighteen feet of water. 
The width of the channel here cannot much exceed 
one hundred and twenty-five yards, if indeed it reach 
that limit. This spit is entirely covered at high water, 
but at low water is seen as a narrow winding bar of a 
little more than a mile and a fifth long, forming a por¬ 
tion of the Great Brewster, and composed of loose and 
shifting materials. Between this point and Lovell’s 
Island is the Black Bock Channel, which here unites 
with the main ship-channel. 

The Commissioners reported in 1860 that the Great 
Brewster, which has been protected by a sea-wall 


5 


34 


only at the end of the East Bluff, was so rapidly 
wearing aw r ay that, during the thirteen years since 
1847, one hundred and fifty thousand square feet of 
its surface had disappeared from the hill; and that, 
whereas it originally measured one hundred and four 
feet in height and thirty-seven acres in area, thirty-two 
acres were now entirely gone, and very soon too little 
of the hill would be left to permit of grading upon 
an inclination suited to preserve its present height. 
Once the island on which this hill stood comprised 
also the Middle Brewster on the north and Lighthouse 
Island on the south. Now there is no connection, 
except in the form of shoals and a reef. The south 
shore of the island had washed away, during the same 
thirteen years, for an average distance of sixty-five or 
seventy feet; the total loss in that time amounting to 
about seventy-five thousand square feet. And not only 
this, but the encroachment had advanced to the base of 
the little hill on the south, which it was rapidly under¬ 
mining. Thus, for want of the protection which a sea¬ 
wall would have given, was destroyed this bold and use¬ 
ful headland, only a shadow of which now survives, and 
from its destruction has grown that dangerous reef, 
Brewster Spit. This spit has risen till its summit is 
nearly dry at high water of low neap tides, and the 
extreme west and highest point has extended to the 
northwest two hundred and fifty feet since 1847. 


35 


A beacon then marked the extremity; but, when 
the “ Spit Lighthouse ” was built, this extremity 
had moved one hundred and fifty feet, encroach¬ 
ing to that amount upon Black Rock Channel. 
In 1860, the point had moved one hundred and 
seventy feet farther, and one half the lighthouse actu¬ 
ally stood beyond the low-water limit. To-day the 

it " 

lighthouse rises not from the spit, but from the water. 

Meantime the sea is washing away the Lighthouse 
Island also, and the United States Lighthouse Inspec¬ 
tor, three years ago, called attention to the danger which 
was threatening Boston Light. Lovell’s Island was 
found to have been washed away on both sides, the 
loss being one hundred and twenty feet on the south 
shore and nearly as much on the north ; this, too, al¬ 
though its total width at this place was less than three 
hundred yards. But at the other end of the island, 
toward the Narrows, this island, too, was found to have 
encroached upon the channel. 

In short, material had been transported from a point 
where it was desirable, and deposited where it was 
prejudicial by the action of strong ebb currents, of 
which a glance at the map will show the working, 
upon the general principles already explained. Wher¬ 
ever the sea-wall existed, not only has it protected the 
island from such abrasion, but it has arrested and 
accumulated large masses of sand and stones, which 


36 


are now acting to guard the island instead of swelling 
the volume of the materials which are actively building 
up reefs and shoals. 

Passing to Gallop’s Island, the low-water line had 
encroached upon the Narrows during the same thirteen 
years by fifty feet; and the same encroachment had 
gone on under water to an extent reducing the average 
soundings by five feet along the shore. 

These are but illustrations of what has been and is 

% 

going on in Boston Harbor. Of course we cannot 
even allude to all; but we have selected these because 
they bound the main channel in a critical place, and 
are encroaching upon it to a serious degree. So, too, 
the passage leading to the ship-channel from Nantas- 
ket Hoads between George’s and Gallop’s islands. In 
their preliminary report the Commissioners stated that, 
whereas formerly a vessel coming up this way from 
Nantasket Roads saw a clear expanse of water through 
between Gallop’s and Lovell’s, the east end of one and 
the southwest extremity of the other have since in¬ 
creased so much that these two points appear to over¬ 
lap, and that the increase of land has occasioned such 
changes in the line of deep water that a channel once 
nearly straight and comparatively easy is now tortuous 
and difficult. This change was due chiefly to the reckless 

removal of the heavier surface material from the east 

0 

end of Gallop’s Island for ballast, thus leaving the 




/ 


lighter material a prey to the waves during storms and 
spring-tides. The light material thus removed was 
transported by the tide to the southeast part of the 
island, there building out a sort of spit, which en¬ 
croaches seriously upon the deep water in an impor¬ 
tant place. Fortunately the counsel of the Commis¬ 
sioners to remove this island from private hands was 
promptly given and promptly followed, and this one 
danger was at last obviated, not too late to avert still 
more serious harm. 

The second report of the Commission describes 
many cases of the destruction of headlands, analogous 
to and equally startling with those we have described. 
We will not dwell upon them, but will content our¬ 
selves with referring to their accounts of the havoc 
going on at Point Allerton, (where only about an acre 
and a half remain out of the forty-five which once 
formed Little Hill, and some fifteen acres of Great 
Hill are already destroyed,) at Nantasket, Long Island 
Head, Winthrop Head, and Deer Island. 

Following the main channel inward, and traversing 

the spacious anchorage called President Loads, whose 

guarding hills and shores are sharing the common fate, 

we finally enter the inner harbor at the straits where 

the several channels unite to pass the narrow entrance 

between Castle and Governor’s islands. There are, of 

ii 

course, water-ways between each of these islands and 


38 


the shore, which exert an important influence upon the 
currents, but the passage between the Castle and South 
Boston is not safe, at low water, for craft drawing over 
four feet; and the channel to the north of Governor’s 
Island is so narrow, intricate, and contorted, as to be 
unsafe for ships under sail. 

The principles already set forth show that, both 
above and below the narrow passage, we ought to 
expect shoals; and, just inside, we actually find the 
channel obstructed by the “ Upper Middle ” bar, while 
the “ Lower Middle ” divides the channel into two 
branches just outside the contraction. The positions 
are just such as to favor accumulation and deposit; 
yet it is probable that these shoals are in fact the 
remains of wasted islands, not removed much below 
the water surface, for the same- reasons that would 
have promoted deposits had no islands existed,— 
yet, washed away above the surface by the agency of 

s 

storms and the undermining power of the waves. 

The Commissioners report that while both the strong 
ebb and flood currents ought to wash away, little by 
little, the clay by which the basis of the Upper Middle 
is formed, the tendency to accumulation in conse¬ 
quence of their insignificant resultant action in a tidal 
day has collected shells and other rolling materials, 
which, in the absence of sufficient power for their per¬ 
manent removal, cover and protect the clay on which 


39 


they rest. The Lower Middle lies between the two 
different channels outside the straits, being west of 
the direct flood channel, and east of the channel into 
which the ebb is thrown by the interruption offered 
by Governor’s Island. 

Were the ebb current of the harbor to flow in one 
channel, instead of being divided into three, it would 
suffice to remove the Upper Middle. Indeed, were the 
outflow north of Governor’s Island checked, which 
might be done without injury to that channel, in fact 
with benefit to it, this result would be obtained ; if 
the outward current were sufficiently increased at any 
regularly recurring interval to wash away the deposit 
of rolling material, this bar would slowly disappear. 
But it is constantly increasing, and is a serious obstacle 
to the channel. The water on the Lower Middle is 
now so shallow and so quiet as actually to be covered 
with an abundant crop of sea-grass, — though situated 
in mid channel, -— the Hood-currents passing, as we 
have already said, on the one side, while the ebb 
passes on the other; the shoaling effect exerted upon 
the ebb by the expansion from out the straits being 
thus, in a measure, counteracted by the momentum of 
the stream. 

Continuing to follow the main channel, and passing 
into the inner harbor, past the Upper Middle bar, we 
next find it obstructed by a knoll which projects into 


40 


it from Bird Island Shoal. Between East Boston and 
Governor’s Island once stood Bird Island, larger than 
Governor’s Island, on which now stands Fort Win- 
throp. Between this and Governor’s Island, where a 
second-rate channel still exists, once flowed a vigorous 
tidal current, forming straits not unlike those between 
Governor’s Island and the Castle ; and between Bird 
Island and East Boston was still another excellent 
water-way, skirting the shore to the eastward of the 
Cunard Wharf, and rendering that a far better site 
for wharves than can be found south of Long Wharf. 
Access to these two ship-channels was supplied by a 
noble avenue, south of Apple Island. 

Bird Island is now a shoal, bare at low tide; and to 
its destruction we owe many of the ills which have 
affected the inner harbor. The expansion of the inner 
harbor, occasioned by its destruction, produced degra¬ 
dation of tidal range. This, and the new fields opened 
for the passage of the tidal currents, so far diminished 
their scouring action that their former channels be¬ 
came places of deposit, and so far altered their direc¬ 
tion that their action has lost much of its beneficial 
influence. The coarse sand has been wasted away, 
and gravel is the only material now left. The lost 
material has all been employed directly in the con¬ 
struction of shoals and spits, and indirectly in aiding 
the growth of still more. And the abrasion which 



41 


now goes on by extraordinary tides while the island 
is submerged, or by storms when the island is bare, 
chiefly results in the deposit of material along its 
margin. The portion above low-water mark will still 
continue to waste, and its component parts be em¬ 
ployed in enlarging the area below that limit until 

it ceases to be exposed at any time of tide. For 

* ♦ 

although the currents may as yet be such as to pre¬ 
clude any deposit of suspended material from forming 
an accumulation, the gravel and larger stones, moved 
by the action of extraordinary currents, will be trans¬ 
ported laterally into deeper water. The spit or knoll 
however, to which we have referred, does not seem 
to be a product of this action. It was probably once 
an integral portion of the island, which the scouring 
action of the joint current of the Charles and Mystic, 
combined with the strong set of the ebb, has long since 
removed. The Commissioners are of opinion, that if 
this obstruction to the channel were dredged up, or 
what would be much cheaper, harrowed up, and suf¬ 
fered to wash away during the ebb, it would not 
reappear. And, although the Commissioners intimate 
nothing of the kind, we cannot avoid the conviction 
that a short sea-wall — built from a point north of the 
highest point of the island, sufficiently far to the east 
to check the scour of the flood tide—would, in con¬ 
nection with a second one, built in a proper curve 


6 



42 


around the western point of the island, to turn part 
of the ebb scour into its former channel to the north, 
and to ward off the remainder from the southern 
shore, result in bringing about an accumulation upon 
this shoal, and even in furnishing a basis for the 
ultimate reclamation of the island, at the same time 
that the channels north and south would be im¬ 
proved. 

The reclamation of Bird Island might even suffice, 
at some future day to re-establish a convenient ship- 
channel north of Governor’s Island. For all along 
the southern bank of the island an accumulating ten¬ 
dency exists even now during flood-tide, and the accu¬ 
mulation is only removed by the action of the ebb. 

The ship channel springs, as has already been ex¬ 
plained, from the confluence of the streams which 
(taken in connection with tidal action) exert, or have 
exerted, a resultant scouring force outward, and from 
similar outward scouring forces arising from predom¬ 
inance of ebb currents over those of flood, owing to 
the forms of the shore lines, and especially those of 
the islands. 

So far as the inner harbor is concerned we have 
the outflow of two rivers, the Charles and the Mystic ; 
and of three tidal reservoirs, — the South Bay, whose 
scour created the deep water once existing between 
South Boston Bridge and Central Wharf; the Back 


43 


Bay, the existence of which rendered the mouth of 
Charles River an estuary; and the broad inlets known 
as Millpond and Miller’s River, on either side of 
Somerville Point and between Charlestown and East 
Cambridge. The discharge of the last two gives its 
value to the wharf frontage of the North End, and to 
the wharves and docks of the Navy Yard, excepting, 
of course, that part which fronts on the Mystic. 

Of these we next propose to speak. 




NUMBER V. 


The upper harbor of Boston owes its existence and 
maintenance, as has been already stated, to the outflow 
of two rivers, — the Charles and the Mystic; and of 
three tidal reservoirs, — the Back Bay, the Millpond, 
and the South Bay. In addition to these, the outer 
harbor is further supported by the outflow of the 
Neponset, the line of whose scour, after furnishing 
the means of access for vessels to the village of 
Neponset and to Commercial Point in Dorchester, 
passes to the westward of Thompson’s Island, and 
contributes to the support both of the “Back Way” 
channel and of the channels leading outward from 
President Roads. The river has, however, no influ¬ 
ence upon the upper harbor, except in so far as it 
obstructs the outflow between Castle Island and South 
Boston Point, — an influence which may, on the whole, 
be regarded as salutary. 

The wharf line of Boston proper, from South Bos¬ 
ton Bridge to Charlestown Bridge, extends along a 
curve of about two miles. Formerly about a mile 
more of wharves existed above South Boston Bridge, 


45 


and yet another between Warren and Cambridge 
Bridges. These are however at present of no com¬ 
mercial value, owing to interruptions inevitably occa¬ 
sioned by the bridges, which became a public necessity 
. as the growth of the City progressed. Moreover there 
can be no reasonable doubt that the wharves now 
accessible to shipping are competent to furnish all 
requisite accommodations, provided that the docks 
do not fill up nor shoals form at their extremities. 
Should the docks fill up, the remedy is easily provided 
at the comparatively small expense of dredging. But 
if the channels of access tend to clog, the case is far 
otherwise, for man cannot long maintain the unequal 
struggle with nature ; and if natural forces cease to 
maintain the channels, commerce will seek other ave¬ 
nues. Our chief concern is with the influences which 
keep the channels open by preventing and removing 
deposit. 

The material for deposit in our harbor is supplied 
from three sources, — the mud and sand brought from 
inland by the outflowing streams, the destruction of 
headlands and islands, and the sewerage of the City,—- 
including all the waste and refuse which is thrown into 
the water. One or more of these sources is always 
actively supplying such material, and the flood tide 
brings all three into action. Wherever slack water 
occurs, at any time of tide, deposits take place rapidly; 


46 


wherever a dock or an inlet affords a nook, whither the 
inflowing water may transport what it holds in suspen¬ 
sion, while the departing tide draws its outflow from 
the surface chiefly, deposits will continually go on, 
although more slowly; wherever a current, bearing 
with it foreign but not floating matter, experiences a 
diminution of velocity, — either in consequence of an 

enlarged avenue for its flow or of a check to its 

% 

momentum arising from some obstacle or some sudden 
alteration of its direction,— the subsidence of the sus¬ 
pended material is equally inevitable. The only possi¬ 
ble preventive of permanent shallowing in such situa¬ 
tions must be sought in an outward scour, adequate to 
remove all these deposits; and this scouring force is 
dependent, as we have seen, upon the excess of the 
momentum of the outflowing current over that of the 
inflowing. Hence a bridge, built on piles only, is often 
adequate to the destruction of a channel, and almost 
invariably produces injury. If, however, instead of 
piles, its base is partly formed by an embankment or 
wall, the first effect must be to cause a diminution in 
the depth of water both above and below those places 
where the bridge acts as a dam, restricting the channel 
to such positions as permit the direct passage of the 
current; and if the dam thus formed crosses tide 
water, the degradation of range within the basin 
which it forms acts to dimmish the force of both 


47 


inward and outward currents, — thus tending to fill 
up the basin and the channel through which the water 
enters and leaves it. 

The current which brings the combined outflows of 
the Back Bay, the Charles River, and the Millpond, 
through the straits between Charlestown and Boston, 
there meets the ebb from the Mystic, which forces 
it back from the East Boston shore, — deflecting its 
direction sufficiently to make its channel skirt the 
wharf line nearly as far as T Wharf; although decided 
deposits along this line have been indicated by each 
survey since 1835. The Mystic outflow, reinforced a 
little by Chelsea Creek, is pressed in like manner 
against the East Boston side, and the two currents 
then pass together outwards, as explained in our 
fourth article. The Fort Point Channel, issuing from 
the South Bay, gives access to the tier of wharves from 
Long Wharf southward, and separates them from the 
South Boston Flats, — the northerly apex of which is 
nearly opposite the dock between Central and India 
wharves; although no part, north of Rowe’s Wharf, is 
absolutely exposed at low water. Were this channel 
to fill up, the line of flats would extend from Long 
Wharf to South Boston Point; and the other outward 
currents would merely suffice to give this line a concave 
form. 

Let us now consider the waters which find their 


48 


outlet between Boston and Charlestown from the estu¬ 
ary of Charles River, consisting of the stream of the 
river itself, and the outflow of the two tidal reservoirs. 
Here we find that the encroachments have been abso¬ 
lutely enormous. Some, like the filling in of the new 
lands, from whose reclamation we hope for much ben¬ 
efit to Boston, are in themselves so great public gains 
that they may well offset considerable detriment; and 
the detriment may indeed be left out of consideration 
when, as in this case, a great portion of it had long 
since been inflicted by the construction of the Milldam. 
So, too, the multiplication of bridges in the most critical 
positions of the channel must be borne as a necessity. 
Even the encroachments on the westerly side of the 
Milldam, which usurp still valuable water area, and 
have the additional disadvantage of destroying the 
beauty of what would otherwise soon have become one 
of the most beautiful avenues in the world, are palli¬ 
ated by the consideration that flats had already formed 
there in the place where many of our citizens once 
knew four navigable channels. 

But what shall we say of the needless encroach¬ 
ments by the railroads between Warren and Cragie’s 
Bridges? For the mere sake of the convenience of 
more land, an enormous amount of water area has 
been here covered over. Without considering the 
amount of solid filling, the forest of piles here driven 


49 


by the tour railroad companies, for purposes not de¬ 
manded by the public need, has sufficed materially to 

diminish the momentum of the current, and has un- 

» 

questionably produced a great degradation of tidal 
range in the basin once known as the Inner Harbor. 
But worse than this, two huge causeways have been 
thrown from East Cambridge in curved lines toward 
the city and tilled in with earth, thus acting as com¬ 
plete dams. The recent conversion of Prison Point 
Bridge into a solid causeway, actually damming up 
the whole of the second tidal reservoir, cannot be 
too deeply lamented. No water communication now 
exists between the sea and the waters lying between 
East Cambridge and Charlestown, except at a single 
drawbridge. A tidal reservoir of great value has 
thus been converted into a mere basin, the rise and 
fall of whose tides is much less than in the harbor, 
which is continually growing shoaler; and the capa¬ 
city of which is, moreover, continually suffering dim¬ 
inution by fillings in with earth. 

Passing on to Cragie’s Bridge, we here find equally 
serious invasions of the water-way by structures pushed 
to the actual verge of the channel. These, like those 
last mentioned and like the very injurious and exten¬ 
sive fillings in at the Cambridgeport end of the Cam¬ 
bridge Bridge, ought never to have been permitted by 
the Legislature. For the sake of present pecuniary 


7 


50 


emolument, it would appear that the future welfare 
of the City has been sacrificed to an extent which 
could not be compensated by manifold the total gains 
of the railroad company and of the individuals con¬ 
cerned. 

In all these serious encroachments there is a 
fourth element of harm to which we have not espe¬ 
cially alluded, although it may be readily inferred 
by those who have perused our summary of general 
principles in former articles. Not merely have the 
two tidal reservoirs been essentially destroyed, — one 
of them without any corresponding public gain, — 
and also the water area of the estuary greatly dimin¬ 
ished; not only, in addition, has the flow of the main 
currents been deliberately obstructed by permanent 
solid structures of earth and stone, built out across 
the directions of their flow; nor is it alone, beside 
these, that so large a mass of open piling has been 
constructed in the straits that the momentum of the 
water is almost entirely destroyed,—but over and above 
all these inexpressible injuries, the currents of the 
ebb and flood are so differently affected by these arti¬ 
ficial structures, that their channels follow different 
paths; and have become so complicated, through con¬ 
tinual deflection by obstacles at different angles with 
their directions, that a new train of peculiar and seri¬ 
ous evils has been originated. 






51 


The reader may naturally inquire, “What is to be 
done?” “ How can all this evil be remedied?” The 
answer is a sad one. It cannot be remedied. And, 
even were private interests made subordinate to public 
ones, and present local , short-lived gain subordinated 
to the permanent welfare of the City, comparatively 

little of the damage could be repaired by the expen- 

11 

diture of a hundred-fold those outlays which have pro¬ 
duced it. Legislatures and lobbymen must bear a 
large share of the heavy responsibility. But this, at 
least, can be done: A public sentiment can be and 
ought to be aroused which should make it disrepu¬ 
table for any man or body of men to commit further 
encroachment, and in any legislator to sanction further 
invasion of the water area around Boston, until some 
competent commission of scientific men has placed 
on record some certificate that the injuries already 
inflicted upon the harbor will not thereby be aug¬ 
mented. And, if their certificate to this effect be 
accompanied with any proviso, the uttermost fulfilment 
of such proviso should be enforced with a determina¬ 
tion and tenacity greater than Shylock’s — 

“If every ducat in six thousand ducats 
Were in six parts, and every part a ducat, 

I would not draw them; I would have my bond.” 

It may well be, indeed it certainly is the case, that 


* 


52 


there are places where the building out of the shore, 
and indeed the redemption of flats, may be harmless,— 
provided that for every step of the encroachment a 
corresponding enlargement of the water capacity at 
some other point could be insured. There are many 
places where, as in the case of Bird Island, already 
considered, an actual Ailing in may be a gain. But 
let us make sure that no more encroachments be 
permitted, unless duly certified to be innocuous; and 
unless the execution of every condition insuring their 
harmlessness be rigorously extorted. Only by the 
overpowering force of public opinion can the course 
of destruction be stayed, so long as men can be found 
who seek private gain at the expense of an unutterably 
greater public loss. 




NUMBER VI. 


There are many important topics connected with 

H 

the physical defence and maintenance of Boston 
Harbor, to which we would gladly advert. But we 
fear to trespass too much upon the reader’s patience, 
lest he cease to be a reader at all. If we can 
but impress those, whose judgment guides the public 
counsels and shapes the public opinion, with a 
sense of the irretrievable injuries already inflicted; 
convince them that these injuries are due to artificial 
influences ; show them how certain ones have been 
brought about; how some can be remedied, some 
obviated, and some prevented, — our object will have 
been attained. And whether this desirable object be 
or be not attained, we desire also, as a Boston boy, 
to express our sense of the services rendered by our 
Mayor in originating, encouraging, and aiding the 
Harbor Commission; to the Commissioners for their 
laborious, gratuitous, and invaluable researches; and 
to the assiduous and skilful engineers and hydro- 
graphers, through whose personal exertions the facts 
have been collected and the results obtained upon 


54 


which all our conclusions must necessarily depend. 
Among these, Mr. Henry Mitchell, of the United 
States Coast Survey, and Mr. A. Boschke, ap¬ 
pear to have been especially prominent. In their 
reports, the Commissioners pay high compliments to 
both of these gentlemen, and state that the mate¬ 
rials for their inquiry into the present regimen of 
the harbor “ are chiefly furnished us through the 
labors and researches of our accomplished colaborer, 
Mr. Mitchell.” 

Among those subjects which furnish a wide and 
interesting field for inquiry, connected with the 
preservation or reclamation of the harbor, are the 
laws which govern the flow of Mystic Pond, and 
the tidal ranges and currents of the Mystic River. 
The discussion of these, in connection with the 
Charlestown Aqueduct, forms the topic of the third 
and most extended report which the Commission 
has yet presented; and has brought to light many 
new and extremely instructive facts relative to the 
nature of its operation as a tidal reservoir; the 
principles which should govern the construction of 
sea-walls; their action in promoting accumulations 
at certain points by the destruction of momentum 
in waters which are transporting material for deposit, 
or by the deflection of a current into a wider or an 
expanding path ; their influence in defending head- 


55 


lands and island shores; their power of creating 
scour in special channels, — all are of great importance 
in their applications to the Outer Harbor. The dis¬ 
tribution and deposit of the sewerage of a great city 
is always an important question, and is especially so 
in our own harbor on account of its peculiar con¬ 
formation. The special effects of the dams, which 
have been or may be constructed across important 
water-ways ; the influences which the Mystic and 
the Neponset respectively exert upon the inner and 
outer harbors; the nature of that action by which 
the outflowing currents of the Charles and the 
Mystic each tend to push back the other against 
the opposite shore; the differences in the epochs 
of the currents which flow from the different outlets 
in the harbor, and give a totally distinct character 
to the lines of deposit and of scour from that which 
would result from simultaneous epochs in their dif¬ 
ferent currents, — all these, and many others like 
them, offer strong temptations to dwell for a while 
on the interesting questions which they present. 
But our present purpose is a limited one, and we 
will therefore confine ourselves to the consideration 
of the Fort Point Channel and the South Boston 
Flats. 

The South Bay was originally a tidal reservoir 
of considerable magnitude. Less than half a cen- 


56 


tury ago, the high spring-tides submerged Boston 
Neck, flowing entirely across Washington Street, 
(then the only avenue,) and rendering the City an 
island. Scarcely thirty years have passed since the 
“ South Cove ” was filled in, embracing most of the 
territory east of Harrison Avenue, south of Beach 
Street, and north of the Dover Street Bridge. Much 
of the area now occupied by land on the South 
Boston shore is also made-land, as is a considerable 
tract at the South End; so that it is probably within 
bounds to say that one third of the area of this basin 
has been filled up, and at least one quarter of the 
remaining water capacity destroyed by deposits, — 
making an actual loss of about one half the cubical 
contents of the basin. No streams of any magnitude 
empty into the South Bay; the most important being 
the brook which rises a little south of Grove Hall, 
and forms the boundary between Koxbury and Dor¬ 
chester. 

The South Bay thus depends upon the tide alone 
for its supply of water ; and the tidal currents have 
here also been obstructed to a very great extent by 
solid embankments, which have been pushed across 
• the water-way, leaving only a sufficient width at the 
drawbridge to permit the passage of vessels. The 
tidal current, thus reduced in volume by the diminu¬ 
tion of the basin, and in intensity by the degradation 


57 


of range within the basin whose entrance is thus 
contracted, is deprived also of its momentum by 
the obstructions offered by the several embankments 
of four bridges, and flows into the harbor with not 
more than a fifth part of the scouring force which 
it possessed thirty years ago. After reaching the 

foot of Summer Street it finds an outlet, and while 

11 

its momentum yet suffices to carry part of the stream 
as far as the end of Long Wharf, a very considerable 
portion of the water finds its way out across the 
flats, where its diminished velocity occasions addi¬ 
tional deposits; so that these flats are growing con¬ 
tinually shoaler and wider. 

The two comparative maps, prepared by the Com¬ 
mission, and showing the changes in the harbor 
between 1835 and 1847, and between 1847 and 
1861, respectively, illustrate these facts with great 
clearness. 

During the former of these periods, the natural 
shore on the East Boston side — which at first pre¬ 
sented a concave front to the impinging waters of 
Charles River, and thus brought the tidal currents 
of the Mystic during ebb into disadvantageous rela¬ 
tions with those from Charles River — was filled 
out by solid wharves to the convex curve of the 
“ Commissioners’ Line; ” thus securing for this re¬ 
gion an excellent channel-way, and forcing the 


Charles River scour along the Boston shore as far 
as T Wharf, to which the opposite currents from 
Fort Point Channel also extended, though not at 
simultaneous epochs. Hence the redemption of this 
land at East Boston exerted a beneficial influence 
on both shores, and a scouring force was brought 
into play, which deepened the stream along the 
front of the wharves, especially from Commercial to 
T Wharf, and abraded the point of the South 
Boston Flats, deepening the water very essentially. 
Unhappily this is the only gain to be recorded, and 
was offset by most calamitous encroachments, both 
by bridges and by too great extension of wharves 
at the North End. And although the improved 
wharf-line at East Boston deepened the water at 
Lewis’s Wharf, and at the extremity of South 

Boston Flats, — all the rest of the inner harbor 
grew shallower inside a line between the wharf 

at the foot of E Street, in South Boston, and the 
Eastern Railroad Wharf, in East Boston. The 

South Boston Flats grew shoaler, and large deposits 
took place in the Fort Point Channel. The solid 
filling in South Boston, consisting of a “ wharf ” 
sixteen hundred feet long where Boston Street and 
Granite Street now are, converted the Fort Point 
Channel for this distance into a canal, through 
which the whole of the current from the South 


59 


Bay flowed, until it found its outlet near where 
the fourth bridge now is. The canal itself was of 
course deepened thereby; but the channel shoaled 
to a more than corresponding extent a little beyond 
the place where the ebb first found opportunity 
for dispersion, — namely, from a point just beyond 
the extremity of this structure, as far northward and 

t* 

eastward as the currents of the Charles and Mystic 
would permit, and along all the docks and wharves 
excepting three as far as Rowe’s Wharf. 

During the second interval, viz: from 1847 to 1861, 
there seems to have been no agency of any sort at 
work to exert a benelicial influence on the harbor; 
unless perhaps that at East Boston, already referred 
to, may have continued to some degree on the East 
Boston shore, north of the Cunard Wharf. All the 
benefit on the Boston side was more than lost again. 
Apart from the encroachments of every kind, already 
described, which had diminished the current from the 
Charles, — the 46 Wharf” in South Boston was extend¬ 
ed one thousand two hundred feet farther, making it 
twenty-eight hundred feet long. Inside of the Central 
Railroad Bridge, the canal thus inclosed has of course 
become deeper, and at its extremity has been formed 
a shoal. But its ebb current being now confined for 
more than half a mile to a nearly straight line, has 
acquired a considerable momentum. The Fort Point 


60 


Channel proper is thus much lengthened, and is, in¬ 
deed, deepened beyond this first shoal; but it has been 
pushed away from the shore, and its stream encoun¬ 
tering the current from the Charles and Mystic, neu¬ 
tralizes their force sufficiently to have formed a second 
and very large shoal which reaches to the upper Mid¬ 
dle Bar, — its base extending from Lewis’s to India 
Wharf. During the interval between the second and 
the third or present survey, every dock but one, and 
the end of every wharf in Boston, north of Battery 
Wharf, has shoaled; and this shoaling is going on 
to-day. The extension of the E Street Wharf, and 
the construction of the wharves at the Grand Junction 
depot, have moved the limit within which the deposits 
are greatest outward to a line drawn from the present 
extremity of the former, to the most easterly of the 
latter. 

In short, we have arrived at this unpalatable ne¬ 
cessity, that we must sacrifice a good deal of what 
remains, in order to make the rest available. The re¬ 
sult at which the Commissioners seem to have arrived 
appears to be, — that our best measure now r is to sur¬ 
render all the water-area covering the South Boston 
Flats, which have already grown so shoal as to be 
worth comparatively little for purposes of navigation, 
and by filling them in up to a line including Castle 
Island, and thus cutting off the water-way between that 


61 


and Dorchester Point, so to direct what elements of 
harbor maintenance are left that they shall keep the 
ship-channel open. To make the Fort Point Channel 
useful, it must now be converted into a canal for a yet 
greater distance, and must be dammed in as far as 
India Wharf. In case it then meets the streams from 
the Charles and Mystic in such a way that their cur¬ 
rents oppose each other, new shoals will arise at the 
point of collision, and deposits off Long and Commer¬ 
cial wharves will still continue to form. Its current 
must consequently be guided into the main channel, 
along a path which shall curve as little and as gently 
as may be, and yet bring the ebb streams together, at 
the smallest possible angle. This implies an extension 
of Central and India wharves, and, perhaps, of Long 
Wharf also. 

The actual cautery is not an agreeable application. 
But Bostonians have brought it upon themselves, and 
although this may not sweeten the remedy, it must 
lead us to bear it with the greatest philosophy in our 
power. We cannot conceal it from ourselves that the 
grand harbor, of which we were so proud, is gone; nor 
are we ignorant of the cause. We must now do our 
best that a second-class harbor shall not degenerate 
into a third-class harbor. Those who have rejoiced 
over the real estate which they have made for them¬ 
selves and their posterity are too much like those 


i 


62 


rulers who have thought they were growing richer by 
the issue of paper money. If they are not on the 
alert, these expensive encroachments will count but 
little for the advantage of those heirs for whom they 
have been willing to sacrifice so much. The rent of 
palatial warehouses in Cranberry Centre would not be 
enormous. 

Now, if South Boston Flats are to be filled in,— 
and filled in they will sooner or later have to be, 
either by the accumulation up to tide-mark through 
natural agencies, or else through human handiwork, 
— there certainly ought to be a compensation some¬ 
where ; and unless the deterioration of our harbor is 
yet to continue, there must be found a new place some¬ 
where for a cubic foot of water to offset every cubic 
foot of water-capacity that is destroyed. And a true 
economy will demand, in addition-, that whatever reser¬ 
voirs are made or deepened or widened shall be so 
devised and constructed that the forces of nature 
brought into play shall tend to their maintenance, 
and not to their destruction. 

In what we have said in these discussions of the 
influences which have brought about the injury, and 
are fast bringing about the destruction of Boston Har¬ 
bor, pecuniary interests must be involved to no small 
extent. Individuals, corporations, speculators, capital¬ 
ists are concerned for or against this or that measure, 




68 


on every side and in every conceivable way. The 
ground is delicate wherever we touch it, since powerful 
interests are affected at every step, which will earnestly 
and obstinately maintain such doctrines as shall appear 
to inure to their advantage. But we have endeavored 
to write as a lover of our beloved city, — having her 

interests in view, and hers only. And in the fullest 

11 

confidence that the candid reader will bear witness to 
the absence of all personal feeling, of all tendency 
to denunciation, of all advocacy of pet schemes, — in 
short, of all motive other than the manifest and avowed 
one, — we will, in closing, only express the fervent 
hope that what we have said may lead to some appre¬ 
ciation of the true state of affairs, — perhaps, indeed, 
stimulate to some judicious exertion; and that part 
of what we have refrained from saying may still be 
inferred from the facts and principles developed. 


64 


P. S. — Since the preceding articles were written, 
the author has obtained through Professor Bache, of 
the Harbor Commission, the following memorandum 
which Mr. Boschke has had the goodness to prepare, 
showing some of the ravages during the period since 
the survey. In the coming winter they will probably 
be, at least, equally serious. 

It may not be amiss in this connection to call atten¬ 
tion to the fact, that an appropriation towards the 
protection of Boston Harbor, which passed the House 
of Representatives, February 28, 1863, in the Civil 
Appropriation Bill, was lost in the Senate, apparently 
without much opposition. 

Cambridge, December, 1863. 


MEMORANDUM. 

Mr. A. Boschke’s resurvey of the Islands in the Outer 
Harbor last summer, show that since 1860 the Great Brews¬ 
ter has suffered from want of protection by sea-walls. The 
southerly headland, a bluff of about forty-five feet high, has 
been reduced by seventy-five feet in its entire length. The 
high bluff facing northwest has suffered an average slide of 
from twenty to thirty feet. This bluff is at its greatest 
elevation over one hundred feet high. A sea-wall on this 
side of the Brewster is also essential, but of equally great 




64 


importance is the grading of the bluff and seeding down in 
grass, and near its base planting of bushes. 

The other Islands have wasted, on an average, by one to 
two feet per year, with occasionally a larger slide of from 
five to ten feet for twenty to forty feet in length. 

On Deer Island the sea-wall requires repairs. In four 
places, measuring an aggregate of four hundred to five hun¬ 
dred feet, the filling has washed out nearly to the foundation, 
and the deck-stones have fallen in. It is evident that sur¬ 
face-water has been directed against these places by gulleys 
in the bluff. Grading the bluff, and seeding down, would 
prevent similar accidents. 


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